[JBL930]

Not to be pedantic, but the G50/50 was only for the 1989 930, so made for one year. The 91 and up 964 Turbos had a G50/52, which had the same ratios as the G50/50, but i'm led to believe the 50/50 is stronger? Not sure why, or even whether that is true? But in most respects the 50/50 and 50/52 are the same.

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Here are the codes and ratios for the other boxes

930 ’76-‘88
1st 2.25 overall 9.50
2nd 1.30 overall 5.51
3rd 0.89 overall 3.77
4th 0.63 overall 2.64
final 4.22

G50/50/52 ’89-‘94
1st 3.15 overall 10.84
2nd 1.79 overall 6.16
3rd 1.27 overall 4.37
4th 0.97 overall 3.34
5th 0.76 overall 2.61
final 3.44

G64/51 ’95-’98
1st 3.82 overall 13.14
2nd 2.15 overall 7.40
3rd 1.56 overall 5.37
4th 1.21 overall 4.16
5th 0.97 overall 3.34
6th 0.75 overall 2.58
final 3.44

G96/50 ’01-present
1st 3.82 overall 13.14
2nd 2.06 overall 7.09
3rd 1.41 overall 4.85
4th 1.12 overall 3.85
5th 0.92 overall 3.16
6th 0.75 overall 2.55
final 3.44

GT3 street car G96/90 ’99-present
1st 3.82 overall 13.14
2nd 2.15 overall 7.40
3rd 1.56 overall 5.37
4th 1.21 overall 4.16
5th 0.97 overall 3.34
6th 0.82 overall 2.82
final 3.44

930 4 speed 930/30-33 ’76-’77 “early” (rod shift)
930 4 speed 930/34-36 ’78-’88 “late” (rod shift)
930 5 speed G50/50 ’89 only (rod shift)
965 5 speed G50/52 ’91-’94 (rod shift)
993 6 speed G64/51 ’95-’98 Twin Turbo (rod shift)
996 6 speed G96/50 ’01 to present Twin Turbo (cable shift)
GT2/GT3/R/RS/CUP* (rod shift up to ’98, cable shift ’98 and on)